Can you find the hidden animal in the picture below?

I am Huge on Sunday and Saturday.
I am small from Tuesday to Thursday.
I do not exist on Monday and Friday.
Who am I?

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

Who can jump higher than a Mountain?

Can you tell a 3D object that has just two surfaces?

What demands an answer, but asks no questions

What will you call your mother's brother's brother-in-law?

There is a shop where written:
Buy 1 for $1
10 for $2
100 for $3
I needed 999 and still only paid $3. How could this be financially viable for the shop-keeper?

Can you calculate the probability of getting a sum of six when a dice is thrown twice?

I am not a bull but I have horns.
I am not an ass but I have a pack saddle.
Wherever I go, I leave silver behind me.

Who am I?